Solar panels are normally carried confined within or on the exterior surface of spacecraft, requiring their deployment into radially projected position after orbit is achieved. While the solar panels may be relatively massive, their deployment occurs under conditions of zero gravity force and without significant resistance to deployment, only that of inertia. Accleration and deceleration forces and the velocity of the panel and its deployment components, in moving from retracted to extended position, may have significant load consequences on the panel and the deployment mechanism. The solar panels may be hinged to the spacecraft or to each other along one panel edge. Normal deployment hinges utilize torsion springs for rotation and structures to absorb the energy at the end of the travel. The torsion spring creates a driving force, which supplies the rotational starting force for the development mechanism, which must be resisted after initiation to fully extended position stop using a separate lock to resecure the panels when fully extended.
While the torsion springs function adequately to drive the hinge elements in desired rotation to deploy the solar panel radially outward of the spacecraft, and the heavier than needed structures have been capable of absorbing the energy at the end of travel, such systems are less than ideal and present no effective control for the initial acceleration, velocity, subsequent deceleration, or positive locking of the hinge structure.
It is, therefore, a primary object of the present invention to provide an improved cam actuated self-locking hinge which obviates the problems of the prior torsion spring rotary hinge structures and which facilitates the adaption of the hinge to different torque characteristics and acceleration rates.
It is a further object of the present invention to provide an improved cam actuated self-locking hinge, particularly adapted as a rotary deployment device to facilitate the deployment of solar panels outwardly of a spacecraft in which the solar panels are subjected to controlled acceleration, velocity, and deceleration with positive locking of the panels at the stroke ends of the rotary deployment device.